Herbicidal trifuluoromethyl-1,3-phenylenediamine compounds

ABSTRACT

N,N&#39;&#39;-Substituted-1,3-phenylenediamine compounds having a trifluoromethyl and a nitro group on the aromatic ring. The compounds are useful as herbicides.

United States Patent William G. Woods Fullerton;

Don L. Hunter, Anaheim; James D. Stone, Whittier; Cecil W. Le Fevre, Anaheim, all

inventors HERBICIDAL TRIFULUOROMETHYL-l,3- PHENYLENEDIAMINE COMPOUNDS 15 Claims, No Drawings u.s.c1 71/121, 71/83, 71/88, 71 92,71 93, 71/94, 71 95, 71/1 1 1, 71/113,71 117,71 118,71 120,260/239,

[51] Int. Cl A0ln9/22, Aoln 13/00 [50] FieldofSearch 7l/l2l,88, 94, 95, 92, 93

[56] References Cited UNITED STATES PATENTS 3,466,329 9/1969 Soper 260/577 Primary Examiner-James 0. Thomas, Jr.

Attorney-James R. Thornton ABSTRACT: N,N'-Substituted-l,B-phenylenediamine compounds having a trifluoromethyl and a nitro group on the aromatic ring. The compounds are useful as herbicides.

HERBICIDAL TRIFULUOROMETHYL- l ,3- PHENYLENEDIAMINE COMPOUNDS This invention relates to novel trifluoromethyl-N-substituted phenylenediamine compounds and their use as herbicides. There is provided by this invention a class of N-substituted-l ,S-phenylenediamine compounds having both a nitro and trifluoromethyl substituent on the aromatic ring which have outstanding herbicidal activity.

The novel compounds of this invention can be defined by the formula wherein R and R are each selected from hydrogen, alkyl, alkenyl, alkynyl, aralkyl, and aryl and R and R are each selected from alkyl, alkenyl, alkynyl, aralkyl, and aryl. Also, R,-R and/or R,,-R,, can represent a portion of a cyclic group suchas an alkylene chain to form a-heterocyclic group containing carbon atoms and optionally other atoms, such as nitrogen, oxygen and sulfur, in addition to the nitrogen atom which is the point of attachment to the aromatic ring.

For convenience in naming the compounds, the amino nitrogen adjacent to the trifluoromethyl group is referred to as N. The amino nitrogen adjacent to the nitro group on the ring is referred to as N. Thus, the nitro substituent is in the 4-position of the aromatic ring and the trifluoromethyl group is in the 6-position of the aromatic ring. It will be noted from the above definition that each amino nitrogen must have at least one substituent thereon, thereby excluding the unsubstituted amino (Ni-l groups.

Typical examples of the groups represented by R,, R R

and R, as defined above are the lower alkyl, lower alkenyl and lower alkynyl groups having up to about eight carbon atoms, including, the cyclic analogues thereof as well as the halo, nitro, hydroxy and lower alkoxy substituted derivatives thereof. Representative groups are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, n-pentyl, n-hexyl, Z-ethylhexyl, n-octyl, allyl, 2-butenyl, Z-butynyl, 3-butynyl, crotyl,

methylallyl, 2-pentynyl, Z-hydroxyethyl, Z-methoxyethyl, 3-

ethoxypropyl, 2-chloroallyl, 2-bromo-allyl, propargyl, 4- chloro-2-butenyl, 4-bromo-l-buteny1, 3-iodo-2-pentenyl, 4- chloro-2-butynyl, 3-nitrobutyl, Z-nitroethyl, cyclohexyl, cyclopropyl, cyclobutyl, cyclohexenyl, and the like.

The substituents on the amino nitrogens according to this invention, can also be an aralkyl or aryl group and especially the monocyclic aralkyl and aryl groups such as benzyl, phen-' ylethyl, phenyl, 2,4-dichlorophenyl, 3-bromophenyl, 4- methoxyphenyl, 3-chloro-4-methylphenyl, 4-nitropheny1, 2,4- dimethylphenyl, 3-fluorophenyl, 4-chlorobenzyl, 2,4-

' dichlorobenzyl, and the like. Thus, the aralkyl and'aryl groups in which Z is an alkylene, alkyleneoxy, alkyleneimino, or alkylenethio group having from about two to six carbon atoms in the chain.

A preferred class of compounds according to this invention are those in which R, and R are each selected from hydrogen,

, alkyl of one to five carbon atoms including the halo-substituted derivatives thereof, and alkenyl of three to five carbon atoms including the halo-substituted derivatives thereof; and R and R, are each selected from alk-yl of one to five carbon atoms, including the halo-substituted derivatives thereof, and alkenyl of three to five carbon atoms including the halo-substituted derivatives thereof. Thus,-representative preferred examples of R R R and R, are methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, sec-pentyl, 2-chloroethyl, 5- bromopentyl, allyl, 2-butenyl, 2chlorallyl, 2-iodoallyl, 3- bromo-2-pentenyl, 4-chloro-2-butenyl, and the like.

The most preferred compounds are those in which the N and N groups are different; that is, the two amino groups are unsymmetrically substituted. In this preferred class of compounds the total number of carbon atoms in the N group is one to four and the total number of carbon atoms in the N group is two to six.

Representative examples of this most preferred class of compounds are ylenediamine ylenediamine ylenediamine N,N-dimethyl-N"-sec-butyl-4-nitro-6-trifluoromethyl-l ,3-

phenylenediamine 1,3-phenylenediamine phenylenediamine N -methyl-N -sec-butyl-4-nitro-6-trifluoromethyl-l ,3-phenylenediamine ylenediamine phenylenediamine phenylenediamine phenylenediamine N -n-propyl-N ,N -diethyl-4-nitro-6-trifluoromethyl-l ,3-

phenylenediamine.

The compounds of this invention are either crystalline solids or high boiling liquids. Generally they are only slightly soluble in water andaremoderately soluble in the usual organic solvents suchas ethanol, acetone, ether and benzene. Thecompounds are readily prepared by reactionof one or two primary or secondary amines with a 2,4-dihalo-5-nitrobenzotrifluoride according to the following equation:

CF I a /NH /NH NO R: R.

2HX NO;

in which X is a" reactive halogen such as'chlorine or bromine and R R R and Rgvcan have the significance previously assigned.

When R and-R are the same asR and R that is'when the, substituted N amino group is the same as the substituted N amino group in the resultant product, the reaction takes place in one step usingan excess, that is, at least 4 moles of amine for each mole of 2,4-dihalo--nitrobenzotrifluoride. When R and R are different from R;, and R the reaction requires two steps in which a different amine is employed in each step. In the first step about 2 moles of the amine forming the N group is reacted with about 1 mole of the 2,4-dihalo-5- nitrobenzotrifluoride. The first halogen atom replaced is that adjacent to the nitro substituent on the aromatic ring. In 15 second step about 2 moles of the amine forming the N group is reacted with the monoamino-substituted compound to form the unsymmetrically substituted phenylenediamine compound. The second reaction takes place preferably in a sealed reaction vessel, such as a sealed tube or an autoclave, to avoid losses of amine and provide easy control of the reaction. In the case of higher boiling amines it is not necessary to use a sealed verted to the amine hydrohalide which can be readily removed.

by washing with water or by filtration after dissolution of the product in a suitable solvent. The desired products can be pu-i' rified by well known procedures such as by recrystallization or.

distillation under reduced pressure.

The intermediate 2,4-dihalo-5-nitrobenzotrifluorides can be prepared by nitration of the corresponding 2,4-dihalobenzotrifluoride such as described by French Patent 745,293 (see Chem. Abstracts 27, 4414).

The following examples describe preparation of representative compounds of this invention but it is to be understood that the invention is not to be limited to the specific examples given.

EXAMPLE I N ,N -dimethyl-4-nitro-o-trifluoromethyll ,3- phenylenediamine A heavy walled glass reaction tube of about 50 ml. capacity was charged with 5 grams of 2,4-dichloro-5- nitrobenzotrifluoride, 30 ml. of ethanol and ml. of liquid methylamine. The reaction tube was sealed and heated in a bath at 100 C. for 184 hours. The cooled reaction tube was then opened and the contents evaporated to dryness to give a yellow-brown solid. To the solid was added 200 ml. of water to dissolve the methylamine hydrochloride and the water-insoluble product was separated therefrom by filtration. After wash ing the solid again with water, it was dissolved in 300 ml. of refluxing 95 percent ethanol. Upon cooling, the product crystallized and was isolated by filtration, obtaining 3.46 grams (76 percent) of the desired product as a yellow, crystalline solid, melting at 21 l-2l2 C.

EXAMPLE 1] v N',N -diethyl-4-nitro-6-trifluoromethyl-l ,3-

phenylenediamine This compound was prepared in a similar manner by reaction of 2,4-dichloro-5-nitrobenzotrifiuoride with ethylamine. The crystalline product was obtained as yellow plates melting at l l51 16.5 C.

EXAMPLE III N,N -bis(dimethyl)-4-nitro-6-trifluoremethyl-1,3- phenylenediamine This compound was prepared in a similar manner by reaction of 2,4-dichloro-5-nitrobenzotrifluoride with ;dimethylamine. The crystalline product melts at 83-84 C.

EXAMPLES IV-XI The following compounds were prepared in a similar; manner by reaction of 2,4-dichloro-5-nitrobenzotrifluoride with the corresponding amine.

IV N{N -di-n-propyl-4-nitro-6-trifluoromethyl-l,3-phenylenediamine; m.p. 63-64C. V N,N -diisopropyl-4-nitro- 6-trifluoromethyl-l,3phenylenediamine; m.p. l2l.5-l23C. VI N,N -dicyclopropyl-4-nitro-o-trifluoromethyl-l,3- phenylenediamine; m.p. l56-157C.

VII N,N -diallyl-4-nitro-6-trifluoromethyl-l,3phenylenediamine; m.p. 74-74.5 C.

VIII N,N -di-n-butyl-4-nitro-6-trifluoromethyl-l,3-phenylenediamine; m.p. 59-59.5 C.

IX N ,N -di-sec-butyl-4-nitro-6-trifluoromethyll ,3-phenylenediamine; b.p. 145-146 C./0.15 mm.

X N ,N -dicyclohexyl-4-nitro-6-trifluoromethyl-l,3-phenylenediamine;m.p. l36.5-l37.5 C.

XI N,N -dibenzyl-4-nitro-6-trifluoromethyl-l,3-phenylenediamine; m.p. l20-l2lC.

EXAMPLE XII N,N -di-methoxyphenyl-4-nitro-6-trifluoromethyl-l ,3- phenylenediamine 2,4-Dichloro-5-nitrobenzotrifluoride was reacted with p- .anisidine dissolved in 1,2-dimethoxyethane in a sealed tube at '150" C. for 75 hours to give the desired product melting at l9l-l92 C., after recrystallization from ethanol.

EXAMPLE XIII N,N-di-n-propyl-5-chloro-2-nitro-4-trifluoromethylaniline A heavy walled glass reaction tube ofapproximately ml. capacity was charged with 35.0 grams (0.1346 mole) of 2,4-

dichloro-S-nitrobenzotrifluoride, 27.24 grams (0.2692 mole) of di-n-propylamine and 60 ml. of ethanol. The tube was sealed and heated in a bath at 100 C. for 4 days. The cooled reaction mixture was then evaporated to dryness to give a residue which was extracted with boiling diethyl ether. The insoluble di-n-propylamine hydrochloride was removed by liltration and washed with additional ether. The combined either filtrates were evaporated to give a liquid residue which was distilled under reduced pressure to give 42 grams of the product as an orange liquid, b.p. l07l 18 C./O.l5 mm.; n 1.5359.

N -ethyl-N ,N -di-n-propyl-4-nitro-6-trifluoromethyl l ,3- phenylenediamine A glass reaction tube was charged with 0.013 mole of N,N- di-n-propyl-5-chloro-2-nitro-4-trifiuoromethylaniline, 0.0536

mole of ethylamine and 20 ml. of ethanol. The tube was sealed and heated in a bath at 100 C. for hours. The contents of the tube were cooled and the ethanol removed by evaporation. The residue was extracted with hot ether and the insoluble amine hydrochloride separated by filtration. The ether filtrate was evaporated to give an oily residue which was distilled under reduced pressure to give the desired product at l32l3 4.5 C./0.l mm.; n" 1.5636.

EXAMPLE XIV N,N,-diethyleneoxy-5-chloro-2-nitro-4-trifluoromethylaniline A solution of 8 grams (0.0308 mole) of 2,4-dichloro-5- nitrobenzotrifluoride and 5.9 grams (0.0677 mole) of morpholine in 35 ml. of ethanol was refluxed for 18 hours. The solvent and excess morpholine were removed under reduced pressure to give a solid residue. The residue was extracted with water and the water-insoluble material recrystallized from aqueous ethanol to give 8.63 grams (70 percent) of product melting at 98-99.5C.

N-ethyl-N ,N diethyleneoxy-4-nitro-o-trifluoromethyl-l ,3- phenylenediamine N,N-diethyleneoxy- 5 -chloro- 2 -nitro- 4 -trifluoromethyl aniline was reacted with ethylamine in a sealed tube as described in example XIII to give the desired product melting at l47l49C.

Representative examples of the many other compounds ,which can be prepared by the above general procedures irez N Z hydrExyethyI)-N -sec-butyl-4-niti b trifluoromethyl- 1,3-phenylenediamine; m.p. 125-l26 C. N-sec-butyl-N -methyl-4-nitro-6-trifluoromethyl-l ,3-phenylenediamine; m.p. 7677 C.

N sec-butyl-N -ethyl-4-nitro-6-trifluoromethyll ,B-phenylenediamine; m.p. 52.5-53.5 C. N -methyl-N ,N -di-n-butyl-4-nitro-6-trifluoromethyl-l ,3- phenylenediamine; b.p. 148-l5 1 C./0.l2 mm. N -methyl-N ,N -pentamethylene-4-nitro-6-trifluoromethyl- 1,3-phenylenediamine;m.p. 93.5-95 c. -N-ethyl-N ,N -[diethylene-(N-methyl)imino]-4-nitro-6- Itrifluoromethyhl,3-phenylenediamine; m.p. 113.5-l14.5 C. N-ethyl-N -ethyl-N -n-butyl-4-nitro-6-trifluoromethyl l ,3- phenylenediamine; b.p. l40 -l.48 'C./O.2 mm.

N ,N -dimethyl-N ,N -diisopropyl-4-nitro-6-trifluoromethyl- LLS-phenylenediamine; m.p. 92-93 C. N -ethyl-N"-tert-butyl-4-nitro-6-trifluoromethyll ,3'- phenylenediamine; m.p. l49-l50 C. 1N'-n-propyl-N -allyl-4-nitro-6 trifluoromethyll ,3-phen- .ylenediamine; m.p. 70.57l.5 C. N-ethyl-N -allyl-4-nitro-6-trifluoromethyl-1,3-phenylenediamine; m.p. 95.5-96.5 C. ,N-methyl-N",N -di-n-propyl-4-nitro-6-trifluoromethyl-l ,3- ;phenylenediamine; m.p. 76.5-77.5 C. N -ethyl-N ,N -dimethyl-4-nitro-6-trifluoromethyl- 1 ,3-phenylenediamine; m.p. lO-l 01 C. iN -allyl-N -ethyl-4-nitro-fi-trifluoromethyl-1-,3-phenylenediamine;m.p. l0l-l02 C. .N -methyl-N -sec-butyl-4-nitro-6-trifluoromethyl1,3-phenylenediamine; m.p. 9596 C. N'-methyl-N ,N"-diethyl-4-nitro-6-trifiuoromethyl-1,3:phenylenediamine; m.p. 6869 C. N -ethyl-N-( 2-chloroallyl )-4-nitro-6-trifluoromethyll ,3- phenylenediamine; m.p. 789-8 1 C. N-ethyl-N -(Z-methoxyethyl)-4-nitro--trifluoromethyl-l ,3- phenylenediamine; m.p. l29.5-l 30.5 C. N -ethyl-N n-octyl-4-nitro-6-trifluoromethyl-l ,3-phenylenediamine; m.p. 41-42 C. N -ethyl-N",N"-di( Z-methoxyethyl )-4-nitro-6-trifluoromethyl-. l,3-phenyle nediamine; b.p. l64.5-165C./0.35 mm. N'-ethyl-N-benzyl-4-nitro-6-trifluoromethyl-l ,3-phenylenediamine; m.p. 97-98 C. N-n-propyl-N,N -diethyl-4-nitro-6-trifluoromethyl-l ,3- phenylenediamine; b.p. l34l 38? C./0.l5-0.20 mm. N -ethyl-N -propargyl-4-nitro-6-trifluoromethyl-l ,3-phenylenediamine;m.p. l60.5-16l.5C. N -methyl-N- -ethyl-N -n-butyl-4-nitro-6-trifluoromethyll ,3- phenylenediamine; b.p. l43 157 C./O .180.20 mm. N -ethyl-N -phenyl-4-nitro--trifluoromethyl-l,3-phenylenediamine; m.p. 9494.5 C. N -ethyl-N",N tetramethylene-4-nitro-6-t1'ifluoromethyll ,3- phenylenediamine; m.p. l30-l3 1 C. N-sec-butyl-N ,N -diethyl-4-nitro-o-trifluoromethyll ,3- phenylenediamine; b.p. 130l36 C./0.l4-0.l5 mm. N -n-propyl-N-ethyl-4-nitro-6-trifluoromethyll ,3-phenylenediamine; m.p. 80-8 1 C. N -n-propyl-N -isopr0pyl'4-nitro-6-trifluoromethyl-1 ,3-phenylenediamine; m.p. 73.5-74.5 C. N,N dimethyl-N ,N -di-n-propyl-4-nitro-6-trifluoromethyl- 1,3-phenylenediamine; b.p. l27-l 32 C./0.l4 mm. N ,N"dimethyl-N ,N -diethyl-4-nitro-6-trifluoromethyl:l ,3-

phenylenediamine; m.p. 47-48 C; N -n-propyl-N ,N -di-n-propyl-4-nitro-6-trifluoromethyll ,3- phenylenediamine; b.p. l43-l5 1 C./O. 18 mm. 4 N -allyl-N ,N -cliethyl-4-nitro-6-trifiuoromethyl-1,3-phenyl pediamine; b.p. l33-l 35.5C./0.l50. l 8 mm.

N-sec-butyl-N ,N -dimethyl-4-nitro-6-trifluoromethyll ,3- phenylenediamine; b.p. C./0.l2 mm.

The compounds of this invention are excellent herbicides and are especially useful as selective. herbicides for controlling weeds in the presence of desirable crops especially the grassy weeds such as, for example, foxtail', water grass, and crabgrass- Many of the compounds of this invention maybe used'in controlling weeds in desirable grassy crops suchas corn and rice, as well as the small grains, andalso the broad leaf crops such as. cotton. and soybeans; Also, many of the preferred. compounds, are effective in-,controlling wild oats which constitute a major problem in. small grain crops such as wheat and barley. Their utility in controllingweeds in grassy crops such as corn, rice, and grains is surprising and unexpected in view of the phytotoxicity of many other aromatic amine derivatives to such grassy crops. It has also been found that the specific phenylenediamines of this invention are much less volatile than many other substituted aromatic amines and will move better in the soil, as well-as possessing better ultravioletlstabilbty.

The compounds can be applied as botha pre-emergence or a,postemergence'treatment; that is they canbe applied to soil in which the weedswill grow or, theycan be used to kill or suppress the growth-ofweeds or to kill or prevent the emergence of seedlings .of undesirable plants. Thus, the compounds can be used to, control the growth of weeds by applying a phytotoxic amount of one or more of the active compounds of this invention to the locus to be protected, that is, soil in which the weeds are growing or willgrow or the foliage of the grow: ing plants. Weeds as used herein is meant to include; any plant growthwhich is undesirable.

Generally an application rate of from about 0.1 to about 25 pounds of one, or more of the active compounds per acre is ef-' fective in controlling plant growth. Preferably an application rate of from aboutOLS toabout-S pounds per= acre is employed.

EXAMPLE XV The compounds, to be tested were evaluated as pre-emen gence herbicides on a broad class of representative weeds and crops. Greenhouse flats were planted to pigweed, cheat, wild oats, foxtail, morning glory, water grass, rice, sugar beets, cotton, corn, barley, and soybeans. On the-same day of planting, the flats were sprayed with an ethanol solution of the compound-to be tested at a rateof one pound per acre. The flats werezkept in the greenhouse and watered when needed. Twenty-two days after treatment, the plants were evaluatedforherbicidal activity and rated ma 0 to 9 scale in which 0 no effect; 5 substantial injury with slight kill and 9 complete kill. The following results were obtained:

Compound 1 Activity 1 PCHW-OFMWRSBOOCRB "This FC EQREF? N -n-propyl-N ,N -diethyI-N'IP 4 0 1 4 2 N -allyl-N ,N -diethyl-NTP 6 1 9 8 1 N -ethyl-N LN -di(2-methoxyethy1)-NIP t. 2 0 4 O N ethyl-N ,N=-tetramethy1ene-NTP t 4 1 1 8 0 N -sec-buty1-N -ethyl-NT 4 1 5 8 1 N -methyI-N ethyl-NTPU 6 3 5 9 0 N -methyl-N -isopropyl-NTP 4 0 5 8 0 N,N -dimethyl-N -n-propyl-NTP 7 3 3 9 0 N -n-propyl-N -ethyl-NTP 4 1 6 9 0 N -n-propy1-N ,N -di-n-pr0py1-NTP 4 2 5 0 3 omhaawoo wponcnouen 1 NTP=4-nitro-6-trifluoromethyl-1,3-phenylenedlamine.

EXAMPLE XVI The compounds to be tested were evaluated as both a preemergence and postemergence treatment on a broad class of weeds and crops. Greenhouse flats were planted to the species the plants had emerged and were about 1 inch in height. These flats were also sprayed with an ethanol solution of the compound at a rate of 2 pounds per acre in order to determine post emergence activity. The flats were kept in the greenhouse and watered when needed. Twenty-two days after treatment,

the flats were evaluated and rated as described in example XV. The following results were obtained:

M- TABLE II Compound A Compound B Compound C Plant Species Pre Post Pre Post Pre Post Pigweed s 4 7 4 9 6 Cheat 2 O 3 0 8 1 Wild oats 9 3 9 3 9 3 Foxtail 9 3 9 5 9 4 Morning glory 4 4 4 3 9 3 Water grass 9 5 8 7 9 8 Rice 0 l 0 0 3 0 Sugar beets 4 4 3 5 6 6 Cotton 0 3 0 2 0 2 Corn 4 2 4 3 9 7 Barley 0 0 0 l 0 0 Soybean 0 0 0 0 2 0 Compound A N3, N -di-n-propyl-4-nitro-6- trifluoromethyl-l ,3-phenylenediamine Compound B N -methyl-N -sec-butyl- 4 -nitro- 6 trifluoromethyl- 1,3 -phenylenediamine Compound C N -methyl-N trifluoromethyl- 1 ,3-phenylenediamine N -diethyl-4-nitro-o- W=Water grass; R= Rice; SB=

TABLE III Actlvlty 3 Compound CH W0 F W CB MI N -ethyl-N ,N -diethyleneoxy-NTP N -ethyl-N -(Z-methoxyethyl)-NTP N -ethyl-N -n-oetyl-NTP N -ethyl-N -benzyl-NTP N ,N -dl(2-methoxyethyl)-NTP N ,N -dlcyclohexyl-NTP X N TP =4-nitro-6-trifluoromethyl-1.3-phenylenedlamlne.

2 CH Cheat; W0 =Wild outs; F Foxtall; W=Water grass; CB =crabi grass; MI=Mlllet. 3 Applied at 22 pounds per acre.

wcncmhe-o:

prob-How EXAMPLE XVII] EXAMPLE XIX Greenhouse flats were planted to millet, oats, soybeans, velvetleaf, sorghum, cheat, pigweed, water grass, crabgrass, foxtail, Johnson grass and ryegrass. On the same day as planting the flats were sprayed with an ethanol-dioxane solution of the 0 compound to be tested at a rate of 5 pounds per acre. The flats were kept in the greenhouse and watered when needed. Twenty-one days after treatment the flats were evaluated and the herbicidal activity rated as described in example XV. The following results were obtained:

TABLE IV Activity 1 Compound 1 ,MI 0 SO V SG CH P W CB F JG RY N -ethy1-N ,N -di(2-methoxyethyl) -NTP 9 4 0 0 4 1 9 9 9 9 9 8 N -ethy1-N ,N -diethyleneoxy-NTP 3 O 0 0 0 0 1 3 0 3 2 0 N -ethyl-N -(2-chloroallyl)-N 'IP 9 3 0 0 4 0 8 7 9 8 8 3 1 NTP:4-nitro-6-trifluoromethyl-l,B-phenylenediarnine. 1 MI=mi1let; O =oats; SO =soybeans; V= velvetleal; S G=sorghum; CH= cheat; P =plgweed; W =water grass;

CB=crabgrass; F=toxtail; JG=Johnson grass; RY=ryegrass.

EXAMPLE xvii Greenhouse flats were planted to cheat, wild oats, foxtail, water grass, crabgrass, and millet. On the same day of planting, the flats were sprayed with an ethanol-dioxane solution of thel compound to be tested at a rate of 25 pounds per acre. The flats were kept in the greenhouse and watered as needed. Twenty-one days after treatment the flats were evaluated and rated as described in example XV. The following results were obtained:

EXAMPLE XX TABLE V Activity 2 Compound 1 P CB W F SG W R JG CO CR B SO N ,N -diethy1-NTP 7 9 3 9 4 8 0 8 0 0 0 1 N ,N -diisopropyl-NTP. 1 3 1 0 3 0 4 0 0 0 0 N ,N -dial1yl-NTP 3 7 4 8 3 8 0 6 0 0 0 0 N ,N -dicyc1opropyl-NTP 0 6 0 6 0 2 0 3 0 0 0 0 N ,N -di-n-propy1-NTP 7 8 3 8 4 6 0 5 0 0 0 0 N ethyl-N -allyl-N'IPnu. 5 8 2 8 2 7 0 6 0 0 1 0 N -ethyl-N ,N -diethyl-NTP 8 8 8 8 4 8 0 8 1 1 1 2 N ethyl-N ,NHii-n-propyLNTP. 7 8 8 8 4 8 0 8 0 0 0 0 N -ethyl-N -phenyl-NTP 0 5 5 4 0 2 0 2 0 0 0 1 1 NTP=4-nitro-6-trifluoromethyl-l,3-phenylenediamine.

Johnson grass; 00 Cotton; CR Corn; B =Barley; S0 Soybean.

Since a relatively small amount of one or more of the active. 1,3-phenylenediamines should be uniformly distributed-over the area to be treated, the compounds preferably are formulated with conventional herbicide carriers, either liquid or solid. Thus, the compounds can be impregnated on or ad-; mixed with a pulverulent solid carrier such as lime, talc, clay, Bentonite, calcium chloride, vermiculite, calcium carbonate, and the like. Alternatively, the compounds can be dissolved or suspended in a liquid carrier such as water, kerosene, alcohols, diesel oil, xylene, benzene, glycols, ketones, and the like. A surfactant preferably is included to aid in dispersion, emulsification and coverage. The surfactant can be ionic or nonionic, and may be liquid or a solid. The use of the term surfactant herein is intended to include such compounds commonly referred to as wetting agents, dispersing agents and emulsifying agents. Typical surfactants include the alkylarylsulfonates, the fatty alcohol sulfates, sodium salt of naphthalenesulfonic acid, alkylaryl polyether alcohols, long chain quaternary ammonium compounds, sodium salts of petroleum-derived alkylsulfonic acids, polyoxyethylene-sorbitan monolaurate, and the like. These dispersing and wetting agents are sold under numerous trademarks and may either be pure compounds, mixtures of compounds of the same, general group, or they may be mixtures of compounds of different classes. Surfactants can also be included in compositions con taining a solid inert carrier.

Concentrated compositions containing the active agent which can be subsequently diluted, as with water, to the desired concentration for application to plants and soil are also provided. The advantages of suchconcentrates are that they are prepared by the manufacturer in a form suchthat the user need only mix them with a locally available carrier, preferably water, thereby keeping shipping costs to a minimum while providing a product which can be used with a minimum of equipment and effort. Such concentrates may contain from about 5 to about 99 percent by weight of one or more of the active 1,3-phenylenediamines with a carrier or; diluent, which may be a solid or liquid. Liquid carriers which are miscible with the active agent or other liquids in which the compound may be suspended or dispersed can be used. A surfactant is also generally included to facilitate such dilution or dispersion in water. However, the surfactant itself may comprise the carrier in such concentrates.

The herbicidal compositions can include other beneficial adjuvants, such as humeetants, oils and contact agents. Also other herbicides, such as the sodium borates, sodium chlorate, chlorophenoxyacetic acids, substituted uracils and ureas, carbamates, amides, and haloalkanoicacids, can be included in the formulation.

The following examples are presented to illustrate the preparation of suitable herbicidal compositions of this invention.

EXAMPLE XXI 5 percent N, N -diethyl-4-nitro-6-trifluoromethyl-l,3- phenylenediamine (powdered) 95 percent Granular clay A granular formulation can be prepared by dry blending the above constituents until uniformly mixed in a rotary mixer. A

W=Water grass; R=Rice; JG=

fine spray of water is sprayed onto the mixture, while tumbling, toadhere the compound to therclay. The material is then air dried. while tumbling to give a granular formulation which can be applied to the soil or vegetation by hand or by a mechanical spreader.

EXAMPLE XXII N di.-n-propl-4-nitro-6- EXAMPLE XXIII 25 percent N -m ethyl-N -sec-butyl-4-nitro-6- trifluoromethyl- 1 ,3-phenylenediamine 5 percent Aromatic sulfonate surfactant 14 percent Chlorobenzene 56 percent Methyl isobutyl ketone The 1,3-phenylenediamine is dissolved in a mixture of chlorobenzene and the ketone to form a concentrated solution. The emulsifying agent is then dissolved and a liquid formulation of an emulsifiable concentrate is obtained.v The emulsifiableconcentrate can be added to water to dilute it to a desired concentration, and then sprayed with conventional.

equipment onto soil or vegetation.

Various changes and modifications of the invention'canbe made and, to. the extent that such variations incorporate the spirit of this invention, they are intended to be includedwithin the scope of the appended claims.

What is claimed is:

1. A herbicidal composition comprising a phytotoxic amount of a compound of the formula where R and R are each selected from hydrogen, lower alkyl, lower alkenyl, lower alkynyl, monocyclic aralkyl, and monocyclic aryl, or R -R and/or R R are a portion of a heterocyclic group having an alkylene linkage of two to six carbon atoms in the ring, and a carrier therefor, said monocyclic aralkyl and monocyclic aryl being unsubstituted or having=nuclear substituents selected from lower alkyl, lower alkoxy, halo and nitro.

2: A herbicidal composition according to claim 1 in which a surfactant is included.

3. A herbicidal composition according to claim 1 in which R and R are each selected from hydrogen, alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms and the halo-substituted derivatives thereof, and R and R are each selected from alkyl of one to five carbon atoms, alkenyl of (IJFa where R and R are each selected from hydrogen, lower alkyl, lower alkenyl, lower alkynyl, monocyclic aralkyl, and monocyclic aryl, and R and R are each selected from lower alkyl, lower alkenyl, lower alkynyl, monocyclic aralkyl, and monocyclic aryl, or R,-R and/or R;,R are a portion of a heterocyclic group having an alkylene linkage of two to six carbon atoms in the ring, said monocyclic aralkyl and monocyclic aryl being unsubstituted or having nuclear substituents selected from lower alkyl, lower alkoxy, halo and nitro.

5. A method according to claim 4 in which R, and R, are

each selected from hydrogen, alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms, and the halo-substituted derivatives thereof, and R and R are each selected from alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms, and the halo-substituted derivatives thereof.

6. A method according to claim 5 in which the total number of carbon atoms represented by R,+R is one to four and the total number of carbon atoms represented by R +R is two to SIX.

7. A method according to claim 5 in which about 0.5 to about 5 pounds of said compound are applied per acre.

8. The method according to claim 7 in which the undesirable plant growth is in the resence of soybeans.

9. The method accor ing to claim 4 in which said compound is applied to the soil.

[0. The method according to claim 4 in which said compound is N'-methyl-N N -di-n-propyl-4-nitro-6- trifluoromethyll ,S-phenylenediamine.

11. The method according to claim 4 in which said compound is N-methyl-N -sec-butyl-4-nitro-fi-trifluoromethyl- 1,3-phenylenediamine.

12. The method according to claim 4 in which said compound is N -methyl-N N -diethyl-4-nitro-6-trifluoromethyl- 1,3-phenylenediamine.

13. The method according to claim 4 in which said compound is N -allyl-N -ethyl-4-nitro-6-trifluoromethyl-l ,3-phenylenediamine.

14. A herbicidal composition according to claim 3 in which a surfactant is included.

15. The method according to claim 7 in which the undesirable plant growth is in the presence of cotton.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,617,250 Dated November 2, 1971 William G. Woods; James D. Stone and Cecil W. LeFevre Inventor(s tified patent It is certified that error appears in the above-idem and that said Letters Patent are hereby corrected as shown below:

Column 10, line 69, after "cyclic aryl," insert --R and R are each selected from lower alkyl, lower alkenyl, lower alkynyl, monocyclic aralkyl, and monocyclic aryl,--.

Signed and sealed this 21st day of January 1975.

(SEAL) Attest:

MoCOY GIBSON JR. C MARSHALL DANN Attestlng Officer Commissioner of Patents USCOMM-DC 60376-F'69 w us GOVEINIAENY PRINTING OFFICE nu 0-365-134 1M PO-1 050 [10-69) 

2. A herbicidal composition according to claim 1 in which a surfactant is included.
 3. A herbicidal composition according to claim 1 in which R1 and R3 are each selected from hydrogen, alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms and the halo-substituted derivatives thereof, and R2 and R4 are each selected from alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms, and the halo-substituted derivatives thereof.
 4. A method for controlling undesirable plant growth which comprises applying to the locus of said plants a phytotoxic amount of a compound of the formula
 5. A method according to claim 4 in which R1 and R3 are each selected from hydrogen, alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms, and the halo-substituted derivatives thereof, and R2 and R4 are each selected from alkyl of one to five carbon atoms, alkenyl of three to five carbon atoms, and the halo-substituted derivatives thereof.
 6. A method according to claim 5 in which the total number of carbon atoms represented by R1+ R2 is one to four and the total number of carbon atoms represented by R3+ R4 is two to six.
 7. A method according to claim 5 in which about 0.5 to about 5 pounds of said compound are applied per acre.
 8. The method according to claim 7 in which the undesirable plant growth is in the presence of soybeans.
 9. The method according to claim 4 in which said compound is applied to the soil.
 10. The method according to claim 4 in which said compound is N1-methyl-N3, N3-di-n-propyl-4-nitro-6-trifluoromethyl-1,3-phenylenediamine.
 11. The method according to claim 4 in which said compound is N1-methyl-N3-sec-butyl-4-nitro-6-trifluoromethyl-1,3-phenylenediamine.
 12. The method according to claim 4 in which said compound is N1-methyl-N3, N3-diethyl-4-nitro-6-trifluoromethyl-1,3-phenylenediamine.
 13. The method according to claim 4 in which said compound is N1-allyl-N3-ethyl-4-nitro-6-trifluoromethyl-1,3-phenylenediamine.
 14. A herbicidal composition according to claim 3 in which a surfactant is included.
 15. The method according to claim 7 in which the undesirable plant growth is in the presence of cotton. 